Authorities investigating the Germanwings crash said in a press conference on Thursday that the co-pilot believed to have deliberately slammed the airplane into the French Alps, Andreas Lubitz, had researched suicide methods and cockpit doors sometime during the week before the crash. German prosecutor Christoph Kumpa said authorities found a tablet in his home that Lubitz had used to explore ways to carry out suicide, ABC News reported, suggesting a degree of premeditation in his actions.

Investigators had discovered the tablet in his Dusseldorf apartment and reconstructed his searches from March 16 to March 23, the day before the crash. Prosecutors' spokesman Ralf Herrenbrueck told the Associated Press in a statement that the 27-year-old co-pilot's search terms included medical treatment and suicide methods, as well as cockpit doors and their security systems.

[He] concerned himself on one hand with medical treatment methods, on the other hand with types and ways of going about a suicide. In addition, on at least one day, [Lubitz] concerned himself with search terms about cockpit doors and their security precautions.

A law enforcement official with knowledge of the investigation told CNN Thursday that Lubitz was seeing at least five, maybe six doctors leading up to the crash, indicating that the pilot was "very afraid" that his medical issues would cost him his pilot's license. According to the CNN source, that fear led to him seeking help from doctor after doctor. Of the five he saw, one was a sleep specialist to help him with his troubles sleeping.

Investigators are currently delving into Lubitz's psychological health. ABC News reported that a special commission of 100 people, known as "Alps," has been put together to investigate the pilot's life as well as to collect evidence that would identify more than 70 German victims.